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Oral administration of Lactobacillus induces cardioprotection.

OBJECTIVES: Our goal was to investigate the potential of oral administration of Lactobacillus to induce cardioprotection against ischemia-reperfusion injury in rat hearts, and to determine whether this protection is associated with myocardial catalase activation and heat shock protein 70 expression. DESIGN: Lactobacillus was administered orally to rats on a daily basis, from 1 to 21 days before global ischemia. Global ischemia was produced by full-stop flow in isolated Langendorff-perfused rat hearts for 20 minutes and was followed by reperfusion. Similarly, saline was administered to control animals. RESULTS: Lactobacillus significantly reduced reperfusion tachyarrhythmia and improved functional recovery of the ischemic rat hearts. These cardioprotective effects were associated with reduction of norepinephrine release at the first minute of reperfusion, activation of myocardial catalase, and overexpression of 70 kd heat stress protein at ischemia and reperfusion (p < 0.05). CONCLUSIONS: Oral administration of Lactobacillus produces marked cardioprotection against ischemia-reperfusion injury. This effect is attributed to activation of the cellular defense system, manifested by activation of the antioxidant pathway, and by expression of protective proteins. Norepinephrine is involved in this process. The results of this study suggest that Lactobacillus, which is generally considered safe, could serve as a basis for the development of a new agent for preventive therapy of various ischemic heart syndromes.

Administration, Oral↗

Probiotics in foods not containing milk or milk constituents, with special reference to Lactobacillus plantarum 299v.

Lactic acid fermentation is the simplest and safest way of preserving food and has probably always been used by humans. Species such as Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus acidophilus, and Lactobacillus salivarius are common in the human mucosa, from the mouth to the rectum. In food, L. paracasei and L. rhamnosus are usually associated with dairy products whereas L. plantarum is found in fermented foods of plant origin. A probiotic food product containing no milk constituent was launched in Sweden in 1994. The product is a lactic acid fermented oatmeal gruel that is mixed in a fruit drink. It contains approximately 5 x 10(10) colony-forming units of L. plantarum 299v/L. The strain L. plantarum 299v originates from the human intestinal mucosa and has been shown in rats to decrease translocation, improve mucosal status, improve liver status, improve the immunologic status of the mucosa, and reduce mucosal inflammation. In humans, L. plantarum 299v can increase the concentration of carboxylic acids in feces and decrease abdominal bloating in patients with irritable bowel disease. It can also decrease fibrinogen concentrations in blood. Should probiotics be administrated through foods, the probiotic organism must remain vigorous in the food until consumption and the food must remain palatable, ie, the food carrier and the organism must suit each other. L. plantarum 299v not only affects the bacterial flora of the intestinal mucosa but may also regulate the host's immunologic defense. The mechanisms involved need to be clarified.

Animals↗

Effect of Lactobacillus GG on intestinal integrity in Malawian children at risk of tropical enteropathy.

BACKGROUND: Tropical enteropathy is an asymptomatic villous atrophy of the small bowel that is prevalent in the developing world and is associated with altered intestinal function and integrity. The histology of tropical enteropathy resembles that seen in small-bowel bacterial overgrowth. OBJECTIVE: This study tested the hypothesis that treatment of 3-5-y-old Malawian children with the probiotic Lactobacillus GG would improve their intestinal function and integrity. DESIGN: Clinically healthy children (n = 164) were enrolled in a placebo-controlled, randomized, double-blind trial. Intestinal function and integrity were measured by using the site-specific sugar-absorption test before and after 30 d of treatment with Lactobacillus GG or placebo. The primary outcomes were the ratios of urinary lactulose to mannitol (L:M) and of urinary sucrose to lactulose (S:L) excretion. RESULTS: Of the 161 children who completed the study, 119 (73%) had tropical enteropathy on enrollment (L:M > 0.10). Children receiving Lactobacillus GG did not differ significantly from the placebo group in the excretion (in % of dose administered) of mannitol (mean +/- SD: 8.9 +/- 4.4 and 8.9 +/- 3.9, respectively), lactulose (0.31 +/- 0.20 and 0.33 +/- 0.23, respectively), or sucrose (0.078 +/- 0.058 and 0.082 +/- 0.075, respectively). L:M and S:L also did not differ significantly between the Lactobacillus and placebo groups (0.19 +/- 0.13 and 0.20 +/- 0.12, respectively, for L:M; 0.58 +/- 0.46 and 0.65 +/- 0.57, respectively, for S:L). CONCLUSION: Administration of Lactobacillus GG for 30 d had no effect on the intestinal integrity of 3-5-y-old Malawian children.

Child, Preschool↗

Lactobacillus flora in the cloaca and vagina of hens and its inhibitory activity against Salmonella enteritidis in vitro.

Lactobacilli in the cloaca and vagina of 40 normal laying hens were investigated quantitatively and qualitatively, and their ability to inhibit growth of Salmonella enteritidis (SE) was examined using a spot-the-lawn technique. All samples of cloacal contents and half the samples of vaginal mucus were positive for lactobacilli. The means +/- SD of total Lactobacillus counts in the cloaca and those in the vagina were log10 5.5 +/- 1.1 and 2.5 +/- 2.6 cfu/g, respectively. In the cloaca, Lactobacillus acidophilus was isolated from 92.5% of hens, and Lactobacillus salivarius was isolated from 85.0% of hens, whereas Lactobacillus fermentum was isolated from only one hen. In the vagina, L. acidophilus and L. salivarius were isolated from 42.5% of hens. In the inhibition assay in vitro, all strains of Lactobacillus from cloacal contents and vaginal mucus inhibited growth of SE. There was a wide range of the inhibitory activity even in the same species. No difference of the growth inhibition zone was observed between lactobacilli from cloaca and those from vagina. The present study suggested that lactobacilli in the cloaca and vagina of hens might have a protective effect against SE colonization.

Animals↗

Lactobacillus GG and acute diarrhoea in young children in the tropics.

A prospective, placebo controlled, triple blind clinical trial was undertaken in Thailand to determine the effect of Lactobacillus GG on recovery from acute diarrhoea in children. Thirty-nine children (mean age = 8 months) were enrolled and following rehydration received either oral Lactobacillus GG (n = 20) as a freeze-dried preparation or placebo (n = 19) twice daily for 2 days. The clinical characteristics of the study groups were similar. There was no significant difference overall in clinical response detected between the study groups. When only those with acute non-bloody diarrhoea (n = 26) were considered, the mean duration of diarrhoea was significantly shorter in the lactobacillus group (1.9 days) than in the placebo group (3.3 days) (P < 0.055). Stool frequency was less on the second day in the lactobacillus group (P < 0.05). The results suggest that Lactobacillus GG accelerates recovery from acute watery diarrhoea in young children in a tropical setting.

Acute Disease↗

Lactobacillus GG administered in oral rehydration solution to children with acute diarrhea: a multicenter European trial.

BACKGROUND: The probiotic Lactobacillus GG is effective in promoting a more rapid recovery of acute, watery diarrhea in children with rotavirus enteritis. Very limited information is available, however, on the potential role of such agents in non-rotaviral diarrheal episodes. Furthermore, no evidence is available concerning the efficacy of Lactobacillus GG administered in the oral rehydration solution during oral rehydration therapy. A multicenter trial was conducted to evaluate the efficacy of Lactobacillus GG administered in the oral rehydration solution to patients with acute-onset diarrhea of all causes. METHODS: Children 1 month to 3 years of age with acute-onset diarrhea were enrolled in a double-blind, placebo-controlled investigation. Patients were randomly allocated to group A, receiving oral rehydration solution plus placebo, or group B, receiving the same preparation but with a live preparation of Lactobacillus GG (at least 10(10) CFU/250 ml). After rehydration in the first 4 to 6 hours, patients were offered their usual feedings plus free access to the same solution until diarrhea stopped. RESULTS: One hundred forty children were enrolled in group A, and 147 in group B. There were no differences at admission between the groups in age, sex, previous types of feeding, previous duration of diarrhea, use of antibiotics, weight, height, weight-height percentile, prevalence of fever, overall status, degree of dehydration, and percentage of in- versus outpatients. Duration of diarrhea after enrollment was 71.9 +/- 35.8 hours in group A versus 58.3 +/- 27.6 hours in group B (mean +/- SD; P = 0.03). In rotavirus-positive children, diarrhea lasted 76.6 +/- 41.6 hours in group A versus 56.2 +/- 16.9 hours in groups B (P < 0.008). Diarrhea lasted longer than 7 days in 10.7% of group A versus 2.7% of group B patients (P < 0.01). Hospital stays were significantly shorter in group B than in group A. CONCLUSIONS: Administering oral rehydration solution containing Lactobacillus GG to children with acute diarrhea is safe and results in shorter duration of diarrhea, less chance of a protracted course, and faster discharge from the hospital.

Acute Disease↗

Comparative sequence analyses of the genes coding for 16S rRNA of Lactobacillus casei-related taxa.

The primary structures of the 16S rRNA genes of the type strains of Lactobacillus casei and related taxa were determined by PCR DNA-sequencing methods. The sequences of Lactobacillus casei, Lactobacillus zeae, Lactobacillus paracasei, and Lactobacillus rhamnosus were different. The Knuc values ranged from 0.0040 to 0.0126. On the basis of the Knuc values and the levels of DNA-DNA relatedness among the strains of these species, the L. casei-related taxa should be classified in the following three species: L. zeae, which includes the type strains of L. zeae and L. casei; a species that includes the strains of L. paracasei and L. casei ATCC 334; and L. rhamnosus.

DNA Primers↗

Lactobacillus coleohominis sp. nov., isolated from human sources.

Four strains of a hitherto unrecognized gram-positive, catalase-negative, facultatively anaerobic, rod-shaped bacterium isolated from human sources were characterized using phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing demonstrated that the bacterium represents a new subline within the Lactobacillus casei/Pediococcus rRNA group of the genus Lactobacillus. The unknown bacterium was readily distinguished from all other described Lactobacillus species and related taxa by biochemical tests and electrophoretic analysis of whole-cell proteins. On the basis of phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Lactobacillus coleohominis sp. nov. The type strain of Lactobacillus coleohominis is CCUG 44007T (= CIP 106820T).

Adult↗

Lactobacillus fuchuensis sp. nov., isolated from vacuum-packaged refrigerated beef.

Four strains of a hitherto unknown bacterium isolated from vacuum-packaged refrigerated beef were characterized by using phenotypic and phylogenetic methods. The novel strains were Gram-positive, catalase-negative, psychrophilic, rod-shaped bacteria with lactic acid-homofermentative mechanism. Comparative 16S rDNA gene sequencing demonstrated that the unknown strains represent a novel subline within the genus Lactobacillus, close to but distinct from Lactobacillus curvatus and Lactobacillus sakei. The unknown strains were readily distinguished from all currently described members of the genus Lactobacillus by biochemical properties and SDS-PAGE whole-cell protein profiles. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Lactobacillus fuchuensis sp. nov. The type strain is strain B5M10T (= JCM 11249T = DSM 14340T).

Animals↗

Molecular analysis of sourdough reveals Lactobacillus mindensis sp. nov.

Genotypic fingerprinting to analyse the bacterial flora of an industrial sourdough revealed a coherent group of strains which could not be associated with a valid species. Comparative 16S rDNA sequence analysis showed that these strains formed a homogeneous cluster distinct from their closest relatives, Lactobacillus farciminis, Lactobacillus alimentarius and Lactobacillus kimchii. To characterize them further, physiological (sugar fermentation, formation of DL-lactate, hydrolysis of arginine, growth temperature, CO2 production) and chemotaxonomic properties have been determined. The DNA G +C content was 37.5 0.2 mol%. The peptidoglycan was of the lysine-D-iso-asparagine (L-Lys-D-Asp) type. The strains were homofermentative, Gram-positive, catalase-negative, non-spore-forming, non-motile rods. They were found as a major stable component of a rye flour sourdough fermentation. Physiological, biochemical as well as genotypic data suggested them to be a new species of the genus Lactobacillus. This was confirmed by DNA-DNA hybridization of genomic DNA, and the name Lactobacillus mindensis is proposed. The type strain of this species is DSM 14500T (=LMG 21508T).

Base Composition↗

Lactobacillus concavus sp. nov., isolated from the walls of a distilled spirit fermenting cellar in China.

Two novel Lactobacillus strains, C-5-1(T) and HB5, were isolated from the walls of a distilled spirit fermenting cellar in Hebei province, China. The strains were Gram-positive, non-spore-forming, non-motile curved rods and were facultatively anaerobic. They produced 5% (-)-D/95% (+)-L lactic acid exclusively from glucose fermentation, but were catalase-negative. Both strains fermented N-acetylglucosamine, arbutin, salicin, cellobiose, maltose, trehalose and beta-gentiobiose. The mean DNA G+C content of the two strains was 46.9+/-0.8 mol% (46.4 mol% for the type strain, C-5-1(T)). Phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain C-5-1(T) was clustered in the Lactobacillus casei/Pediococcus phylogenetic group and was closely related to Pediococcus dextrinicus JCM 5887(T) (97.9% similarity), followed by Lactobacillus algidus JCM 10491(T) (93.9% similarity). The DNA-DNA relatedness between the type strain C-5-1(T) and P. dextrinicus JCM 5887(T) and L. algidus JCM 10491(T) was only 5.4 and 4.3%, respectively. Therefore, based on phenotypic, genotypic and phylogenetic analyses, a novel Lactobacillus species, Lactobacillus concavus sp. nov., is proposed. The type strain is C-5-1(T) (=AS 1.5017(T)=LMG 22739(T)).

Base Composition↗

Lactobacillus vini sp. nov., a wine lactic acid bacterium homofermentative for pentoses.

Six strains with more than 99.5 % 16S rRNA gene sequence similarity, identical internal spacer region profiles and restriction analysis of the amplified 16S rRNA gene patterns were isolated from fermenting grape musts during independent studies carried out in France and Spain many years apart. Strains are Gram-positive, motile, facultatively anaerobic rods that do not exhibit catalase activity and have the ability to utilize pentose sugars (ribose and/or l-arabinose), although they are homofermentative bacteria. Strains ferment pentoses exclusively yielding lactic acid as the end product. A broad set of molecular techniques has been applied to characterize these strains and the results show a high degree of genotypical congruence, sharing identical profiles with 16S rRNA-based techniques. Phylogenetic analysis based on 16S rRNA gene sequences placed these strains within the genus Lactobacillus, closely related to Lactobacillus mali, Lactobacillus nagelii and Lactobacillus satsumensis (with approximately 95 % sequence similarity). DNA-DNA hybridization experiments confirmed the independent status at the species level of these fermenting grape-musts strains. Phenotypically they can be distinguished from the closest relatives by several traits such as growth temperatures and fermentation of carbohydrates. The name Lactobacillus vini sp. nov. is proposed, with strain Mont 4T (= DSM 20605T = CECT 5924T) as the type strain.

Fermentation↗

Diversity of the genus Lactobacillus revealed by comparative genomics of five species.

The genus Lactobacillus contains over 80 recognized species, and is characterized by a high level of diversity, reflected in its complex phylogeny. The authors' recent determination of the genome sequence of Lactobacillus salivarius means that five complete genomes of Lactobacillus species are available for comparative genomics: L. salivarius, L. plantarum, L. acidophilus, L. johnsonii and L. sakei. This paper now shows that there is no extensive synteny of the genome sequences of these five lactobacilli. Phylogeny based on whole-genome alignments suggested that L. salivarius was closer to L. plantarum than to L. sakei, which was closest to Enterococcus faecalis, in contrast to 16S rRNA gene relatedness. A total of 593 orthologues common to all five species were identified. Species relatedness based on this protein set was largely concordant with genome synteny-based relatedness. A Lactobacillus supertree, combining individual phylogenetic trees from each of 354 core proteins, had four main branches, comprising L. salivarius-L. plantarum; L. sakei; E. faecalis; and L. acidophilus-L. johnsonii. The extreme divergence of the Lactobacillus genomes analysed supports the recognition of new subgeneric divisions.

Genes, Bacterial↗

Efficacy of Lactobacillus GG in maintaining remission of ulcerative colitis.

BACKGROUND: Aminosalicylates are the mainstay of therapy to prevent relapse of quiescent ulcerative colitis. The rationale for using probiotics is based on the evidence implicating intestinal bacteria in the pathogenesis of this disorder. AIM: To evaluate the efficacy of Lactobacillus GG alone or in combination with mesalazine vs. mesalazine as maintenance treatment in ulcerative colitis. PATIENTS AND METHODS: 187 ulcerative colitis patients with quiescent disease were randomized to receive Lactobacillus GG 18 x 10(9) viable bacteria/day (65 patients), mesalazine 2400 mg/day (60 patients) or Lactobacillus GG + mesalazine (62 patients). Disease activity index, endoscopic and histological scores were determined at 0, 6 and 12 months and in case of relapse. The primary end point was to evaluate sustained remission. RESULTS: Overall analysis showed no difference in relapse rate at 6 (P = 0.44) and 12 months (P = 0.77) among the three treatment groups. However, the treatment with Lactobacillus GG seems to be more effective than standard treatment with mesalazine in prolonging the relapse-free time (P < 0.05). CONCLUSIONS: Lactobacillus GG seems to be effective and safe for maintaining remission in patients with ulcerative colitis, and it could represent a good therapeutic option for preventing relapse in this group of patients.

Adult↗

Antimicrobial activity of lactic acid bacteria isolated from sour doughs: purification and characterization of bavaricin A, a bacteriocin produced by Lactobacillus bavaricus MI401.

Three hundred and thirty-five lactic acid bacteria were isolated from sour doughs and screened for antagonistic activity. Of these 145 showed activity against one or several of the indicator strains used in the screening. The antimicrobial activity of 18 isolates were due to a proteinaceous compound. These 18 isolates belonged to three different Lactobacillus species: Lactobacillus bavaricus, Lactobacillus curvatus and Lactobacillus plantarum. The spectrum of antimicrobial activity for the three species suggested that the inhibitory components were different. The inhibitory compound from Lact. bavaricus MI401 was chosen for further study. The proteinaceous nature, antimicrobial activity against closely-related species, heat resistance and sensitivity to alkaline treatment strongly indicated that this substance was a bacteriocin, which we designated bavaricin A. The bacteriocin was purified to homogeneity by ammonium sulphate precipitation, ion exchange, hydrophobic interaction and reverse-phase chromatography. The purification resulted in 193,000-fold increase in specific activity. SDS-PAGE of bavaricin A showed a molecular weight of 3500-4000 Da. By amino acid sequencing 41 amino acids were determined. Bavaricin A had a bactericidal mode of action and inhibited nine out of 10 Listeria monocytogenes. Lactobacillus bavaricus MI401 produced bavaricin A at temperatures from 4 degrees C to 30 degrees C. The production of active bavaracin A was inhibited at increasing sodium chloride concentration. In the presence of 3% sodium chloride at 4 degrees C no active bavaricin A could be detected. Nitrite (100 ppm) did not affect the production of active bavaricin A.

Amino Acid Sequence↗

Numerical taxonomy of Lactobacillus spp. associated with healthy and diseased mucosa of the human intestines.

Two-hundred and fifty Lactobacillus strains isolated from healthy and diseased mucosa of human intestines of 75 individuals and 49 reference strains were phenotypically classified using 49 unit characters. Data were processed by the Jaccard (SJ) and Simple Matching (SSM) coefficients, and unweighted pair group algorithm with arithmetic averages. Seventeen major clusters were defined at the 76% SJ-similarity level which approximately correspond to the SSM-level of 91%. Seven clusters could be identified: Lactobacillus plantarum (isolates recovered from 5% of the patients), Lact. casei subsp. rhamnosus (17% of the patients), Lact. casei subsp. pseudoplantarum (5% of the patients), Leuconostoc mesenteroides subsp. mesenteroides (3% of the patients), Lact. buchneri (4% of patients), Lact. reuteri (4% of the patients) and Lact. salivarius subsp. salivarius (9% of the patients). Unassigned clusters 1 and 3 both contained homofermentative Lactobacillus strains. Cluster 1 included the type strains of Lact. crispatus, Lact. acidophilus, Lact. jensenii and Lact. gasseri, and cluster 3, the type strains of Lact. delbrueckii subsp. lactis, Lact. agilis and Lact. casei subsp. tolerans. Clusters 1 and 3 were found in 15% and 25% of the patients, respectively. Unassigned clusters 2, 6, 7, 8 and 10 contained homofermentative Lactobacillus strains but no reference strains. Clusters 11, 12, 15 and 17 were made up of heterofermentative Lactobacillus strains but no reference strains. Phenotypical characteristics of the clusters are given. No obvious trends in species (cluster) composition between different intestinal locations could be noted. Most clusters contained isolates from both diseased and healthy mucosa. Exceptions were cluster 15 and cluster 17 which only included isolates from healthy mucosa, and cluster 11 which only included isolates from diseased mucosa. Cluster 15 was isolated in 12% of the patients, and cluster 11 in 8%.

Classification↗

Protective role of supplement with foreign Bifidobacterium and Lactobacillus in experimental hepatic ischemia-reperfusion injury.

BACKGROUND AND AIM: Intestinal microflora play a crucial role in some severe liver diseases. The purpose of this study was to evaluate the effects of a Lactobacillus strain and a Bifidobacterium strain on ischemia-reperfusion (I/R) liver injury. METHODS: Rats were divided into six groups. Each group received either Bifidobacterium Catenulatum ZYB0401; Lactobacillus Fermentum ZYL0401; a mixture of these two bacterial strains; gentamicin; or saline by daily gavage for 7 days. On the sixth day, all rats, except those in the control group, were subjected to 20 min of liver ischemia. After 22 h of hepatic reperfusion, liver enzymes and histology, malondialdehyde (MDA), superoxide dismutase (SOD), endotoxemia, serum tumor necrosis factor-alpha (TNF-alpha), intestinal bacteria, intestinal mucosal ultrastructure, and bacterial translocation were studied. RESULTS: All administered bacteria increased intestinal Bifidobacterium and Lactobacillus, decreased endotoxemia (P < 0.01), alanine aminotransferase (ALT) (P < 0.01), and markedly ameliorated liver histology and intestinal mucosal ultrastructure. Only rats treated with Bifidobacterium Catenulatum ZYB0401 and Lactobacillus Fermentum ZYL0401 showed reduced incidence of bacterial translocation to the kidney (P < 0.05), associated with decreased serum TNF-alpha and liver MDA (P < 0.05) and increased liver SOD (P < 0.05) compared to the I/R group. Gentamicin decreased almost all kinds of intestinal bacteria (P < 0.01) and decreased ALT (P < 0.01) and serum TNF-alpha, but failed to reduce both endotoxemia and the incidence of bacterial translocation and had no effects on liver MDA and SOD. CONCLUSION: Bifidobacterium Catenulatum ZYB0401 in combination with Lactobacillus Fermentum ZYL0401 could be useful in restoring intestinal microflora and in preventing liver injury in hepatic I/R of rats.

Animals↗

Aggregation-promoting factor in human vaginal Lactobacillus strains.

A total of 60 Lactobacillus sp. strains were examined for expression of auto-aggregation and cell surface hydrophobicity. Isolates were obtained from the vagina of healthy women (n = 20). The results obtained showed that the occurrence of cell surface hydrophobicity correlated with auto-aggregative activity in 12 homofermentative Lactobacillus sp. strains. The aggregation mechanism was mediated by the presence of an aggregation promoting factor (APF) in one Lactobacillus sp. strain, HV 142. APF was confirmed by DNA hybridisation with a 1.3 kb PstI DNA fragment of recombinant plasmid pFDS containing the reading open frame of the APF gene derived from Lactobacillus plantarum 4B2. Coaggregation activity was seen in three strains of auto-aggregative human vaginal lactobacilli and five strains of P-fimbriated uropathogenic Escherichia coli. Moreover, one of four Lactobacillus sp. strains (HV 389) aggregated with two of five E. coli tested. These results suggest that APF producing lactobacilli could represent a further mechanism in the interaction of commensal microflora with strains of uropathogenic E. coli.

DNA, Bacterial↗